The Federalist Papers are a series of eighty five essays written by James Madison, Alexander Hamilton and Jon Jay. They were written to urge New Yorkers to elect state delegates who would support ratification of the new U.S. Constitution. The new Constitution had been produced by the Constitutional Convention in Philadelphia that took place between May and September 1787. The Federalist Papers themselves were published between October 1787 and May 1788 in various newspapers in New York, which was the capital of the United States at that time. Even back then, people knew of the significance of the political theory advanced in these essays. In fact, none other than Thomas Jefferson went so far as to call them "the best commentary of the principles of government which was ever written." Each essay written anonymously by one of the three men named above and signed under the pen name "Publius." Hamilton chose that name in honor of Publius Valerius, an instrumental founder of the Roman Republic. While we have a good guess as to which of Madison, Hamilton and Jay wrote each essay, the authorship of each one has never been definitively determined. In this booklet, select portions of Federalist Papers 1, 2, 10, 14, 39, 51 and 78 have been reproduced in plain English to provide some understanding of the political theory underlying them and the U.S. Constitution itself. However, the reader is urged to consult the actual Federalist Papers to gain a fuller understanding of the reasons for U.S. Constitution, including the broad concepts embodied in it as well as specific reasons for certain powers granted to each one of the three branches of Federal government.